Field of the Invention
The present invention relates to a printed wiring board having through hole conductors formed by filling through holes with plating.
Description of Background Art
Japanese Patent Laid-Open Publication No. 2012-69926 describes a printed wiring board in which through hole conductors are formed by irradiating laser from both sides of a core substrate to form through holes each having a central constricted shape that decreases in diameter from both sides toward a center and by filling the through holes with plating.